Dielectric, pyroelectric and polarization behavior of polyvinylidene fluoride (PVDF) - Gold nanoparticles (AuNPs) nanocomposites

In this study, the polymorphism of poly (vinylidene fluoride) (PVDF) was control by gold nanoparticles (AuNPs). Simple one step method was used for synthesis of AuNPs using HAuC1(4)center dot 3H(2)O, and N, N-dimethylforrnamide (DMF). The AuNPs of size 20-30 rim have been prepared by chemical method. DMF was act as reducing agent and solvent of PVDF. The circular samples of diameter 3.5 cm and thickness 10-25 mu m were prepared. It has been observed that AuNPs modify the structural morphology of PVDF. The beta-phase of PVDF was modified due to interaction between electric charge at the surface of AuNPs and CF2 dipoles. This is further verified by increase of remanent polarization in P-E loop. XRD spectra address the crystallographic phase identification of PVDF in presence of AuNPS. The AuNPs in PVDF matrix significantly enhances 72.2% expansion of remanent polarization (P-r), 19.23% depletion of coercive field (E-c) and 70-100% expansion of shifting speed of the ferroelectric polarization. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) of pristine and NPs mixed PVDF illustrates the structural properties and reason of enhanced ferroelectric properties.